Both public and private communications switching networks are arranged as groups of interconnected switching points. A local service provider maintains a network of interconnected switching points to provide service to its customers. The switching points are coupled at transfer points and each switching point serves a number of connected devices, such as telephones, terminals, and computers. To establish communications between two devices, an originating device dials a number identifying a destination device. The interconnected switching points route the call to the called party in accordance with the dialed number.
Under certain conditions, namely when a destination device is flooded by communications traffic from an exceedingly large number of originating devices, the switching point connected to that destination device can experience an overloaded condition. Such an overloaded condition may be referred to as focused overload. Excessive traffic to a specific destination device can have an adverse effect on the performance of a local service provider's telecommunications network. In particular, excessive traffic may cause network congestion, the failure of resident applications at switching points, or complete element failure at the switching point closest to the destination device. Other network devices and/or connections may be similarly overloaded or have their performance interrupted during excessive communications traffic to a single destination device.
Examples of events resulting in excessive communications traffic to a single device include, for example, calls placed to a specific number during radio contests, calls placed to government, administration, or public service organizations during natural disasters, and other unannounced or unpredicted large call volume events. Call control systems such as Automatic Code Gapping are currently available to handle excessive amounts of communications traffic to a single number if the occurrence of such large call volume events are either planned, predicted, or detected. Problems arise, however, when a large call volume event to a single destination device occurs without proper planning or adequate determination.